Background & Aims: Mucins are high-molecular-weight glycoproteins that protect the gastric epithelium. Previous data suggested that gastric surface-type mucin is decreased in Helicobacter pylori-infected patients and restored after eradication of the infection. Our aim was to determine the effect of H. pylori on mucin synthesis in cultured gastric epithelial cells.
Methods: Mucin synthesis was measured by labeling with [(3)H]glucosamine and size-exclusion chromatography. Expression of MUC5AC and MUC1 mucin protein antigens was quantitated by Western blot analysis.
Results: Mucin synthesis was inhibited more than 80% when KATO III cells were incubated with H. pylori, with no effect on mucin secretion or degradation. Inhibition was rapid (4 hours), partially reversible, dependent on concentration of bacteria, and associated with the insoluble membrane fraction. H. pylori decreased levels of MUC5AC and MUC1 mucins. MUC1 inhibition was half-maximal by 4 hours and partially reversed by 24 hours, but the decrease in MUC5AC was less rapid and not reversible within 24 hours.
Conclusions: H. pylori inhibits total mucin synthesis in vitro and decreases the expression of MUC5AC and MUC1. A decrease in gastric mucin synthesis in vivo may disrupt the protective surface mucin layer.
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http://dx.doi.org/10.1016/s0016-5085(00)70360-x | DOI Listing |
JACS Au
January 2025
UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal.
The mucin -glycan sialyl Tn antigen (sTn, Neu5Acα2-6GalNAcα1--Ser/Thr) is an antigen associated with different types of cancers, often linked with a higher risk of metastasis and poor prognosis. Despite efforts to develop anti-sTn antibodies with high specificity for diagnostics and immunotherapy, challenges in eliciting high-affinity antibodies for glycan structures have limited their effectiveness, leading to low titers and short protection durations. Experimental structural insights into anti-sTn antibody specificity are lacking, hindering their optimization for cancer cell recognition.
View Article and Find Full Text PDFBMC Med Genomics
January 2025
Department of Hepatobiliary Pancreatic Surgery, Shenzhen People's Hospital, No.1017 Dongmen North Road, Shenzhen, 518020, Guangdong Province, China.
Background: Gallstones, a common surgical condition globally, affect around 20% of patients. The development of gallstones is linked to abnormal cholesterol and bilirubin metabolism, reduced gallbladder function, insulin resistance, biliary infections, and genetic factors. In addition to these factors, research has shown that mucins play a role in gallstone formation.
View Article and Find Full Text PDFSci Rep
January 2025
School of Health Preservation and Rehabilitation, Chengdu University of TCM, Shierqiao Road, Chengdu, 610075, Sichuan, People's Republic of China.
Despite the established link between chronic high salt diet (HSD) and an increase in gut inflammation, the effect of HSD on the integrity of the intestinal barrier remains understudied. The present study aims to investigate the impact of HSD on the intestinal barrier in rats, encompassing its mechanical, mucous, and immune components. Expression levels of intestinal tight junction proteins and mucin-2 (MUC2) in SD rats were analyzed using immunofluorescence.
View Article and Find Full Text PDFJ Immunother Cancer
January 2025
Heidelberg University Hospital Department of Hematology Oncology and Rheumatology, Heidelberg, Germany
Bispecific antibodies (BsAb) have emerged as a leading treatment modality in patients suffering from B-cell non-Hodgkin's lymphoma (B-NHL). However, treatment failure is common and may potentially be attributed to pre-existing or emerging T-cell exhaustion. CD39 catalyzes-together with CD73-the hydrolysis of immunogenic ATP into immunosuppressive adenosine and thus actively promotes an immunosuppressive micromilieu.
View Article and Find Full Text PDFMicrobiome
January 2025
Key Laboratory for Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, China.
Background: The microbes residing in ruminant gastrointestinal tracts play a crucial role in converting plant biomass to volatile fatty acids, which serve as the primary energy source for ruminants. This gastrointestinal tract comprises a foregut (rumen) and hindgut (cecum and colon), which differ in structures and functions, particularly with respect to feed digestion and fermentation. While the rumen microbiome has been extensively studied, the cecal microbiome remains much less investigated and understood, especially concerning the assembling microbial communities and overriding pathways of hydrogen metabolism.
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